Shocktech Super Fly Bolt
Halo B w/rip drive
I got this bolt slightly used from a guy I played with and I think its pretty good. To be honest, I don't see that much actual performance difference but I do think that it really does help prolong the life of your ball detents. Also, I like the all delrin just because it is self lubricating and thus, one less thing for me worry about when I am playing. Plus if I have to clean the bore at all, I don't have to worry about any o-rings.
I think its bolt is pretty good. It does not greatly improve or destroy your performance but if you like all delrin (no o-rings) and ball detent grooves, give this bolt a look.